After the change to wintertime in Germany my system refuses to recognize this fact. Everytime I start the machine i have to controll the time and have to correct it. ( ... to go one hour back ...) It doesn't matter if I activate the auto-mode or if I'm set the time manually. The Time and Date Zone is set to Berlin/Germany.

If you activate the automatic time getting it might take a few seconds to connect to the internet and change the time especially if your Mainboard has the wrong set.
Though if Berlin timezone is set it should not do this. Is the date set up correctly?